<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css">
		.father{
			width: 500px;
			height: 300px;
			background: #eee;
			overflow: hidden;
		}
		.son{
			width: 100px;
			height: 100px;
			background: red;
			margin-top:50px;


	</style>
</head>
<body>
	<div class="father">
		<div class="son">
		</div>
	</div>
</body>
</html>